Reamer



M. C. DAW

Dec. 24, l 92 9.

REAMER Filed Aug. 18. 1926 2 Sheets-Sheet l Dec. 24, 1929. M. c. DAW 1,740,647

I REAMER Filed Aug. 18. 1926 2 Sheets-Sheet 2 Patented Dec. 24, 1929 UMTEP STATE ere 9- BATENT OFFICE new, or nns r e nvEjLnunQ oiiro, AssIe von To run KELLY REAMEB -9l414 F P Y P WP A lY N OF H REAMER This invention relates to reamers of the adjustable type and an important object is t oprovide simple and easily adjusted means whereby the blades may be securely held in '75 placeto resist the't'endency of the same to spring while'in use and to shift especially when thereamer is being withdrawn from a piece of worksuch as a long bronze bushing which heats up" and contracts behind the '1 reamer." i

"A further and equally important object is to provide an adjustableieamer which may be manufactured and maintained Without a' substantial departure from established machineshop practice'and in which the 'arra'ngement and construction of parts is such that the same may be made on a production basis at a comparatively low cost.

Other objects and advantages will be ap- Z parentduringthecourse of the following deseriptionf" I In the accompanying drawings forming a part of this application and in which like nuinerals are employ d to designate like parts throughout the same, I

' Figure 1 is a perspective of a reamer constructed in accordance with the invention;

Figure 2 is an end view of the same, parts being shown in section Figure 8' is' a longitudinal sectional View through the reamerf i V Figure 4 is a group perspective illustrating one of the blades andthe holding means therefor;

i s? "Figure 5 is a side elevation ofa heavy duty reamer embodying the invention;

' Figure 6 is-an end' View of a reamer in which the blades and the retaining means therefor "are'sli'ghtly modified;

-- Figure 7 is a group perspective illustrating one -of the"bla'des andthe' hol'ding means therefor illustrated inFi'gure 6; t "Figure 8 is a detailed sectional view through the reanier illustrated in Figure 6.

Iuthe'drawing, the numeral 5 designates a body of any 'stylehaving a pluralityof longitudinal blade receiying surface grooves an a y e pen-as und he-rear ends 0 the n ,"and "ea h haying a shoulder69'at-one I *siawhi'ch issubstantia'l'ly parallel tht e known, engaged with the adjusting nut to told the same firmly in place. As well known in the art theblades 7 are adjustable longitudinally in the gradually deepening grooves to compensate for normal or abnormal wear and to permit of variations within reasonable limits of the cutting diameter of the reamer. Attention is directed to Figure 4 which illustrates that each blade 7 has the base portion thereof widened and beveled to provide a beveled contact surface or shoulder 10 against which the beveled edge of a locking and binding strip 12 is engaged. It will be seen that the shoulder 10 is of the same width throughout and that the edges of the same extend approximately parallel to the land of the blade for engagement by the beveled edge of the locking and binding strip 12. Of course, the blade is gradually increased in its radial dimension toward the rear end thereof te dispose the land of the blade somewhere near parallel to the axis of the reamer and thus the beveled shoulder 12 is not in a plane parallel to the bottom edge of the blade.

" Each retaining strip 12 is adapted to be firmly wedged between the beveled shoulder 10 and one side wall of the groove above slot shoulder '6 by means of locking screws 15 which as clearly illustrated in Figure 2 are adapted to be threaded into said slot shoulder 6 and the body. It is intended that each locking strip 12 should have a tight fit in the space between the beveled shoulder 10 and one side wall of the groove so that when the screws 15 are applied and tightened the blades will be securely held in place against the strainto' which the same are subjected during use. More specifically, since each strip 12 and its beveled blade shoulder 10 have their edges parallel with the land or cutting edge of the blade, the latter, when screws 15 are tigh en will n t nly be tightly wedged again t t e bottem 9 the s o 6 and gainst the slot wall opposite the strip, furthermore the blade Will/be ;-p ositively locked n t rem hi l t r ebiiwslyifd lows, because the plane of the slot bottom in tersects the plane in which the strip 12 lies. Figure 1 illustrates that the strips 12 are in engagement with the blades for the major portions of the lengths of the blades so that the blades are firmly anchored in place. It is especially important to note that the looking and binding strips are engaged with the blades adjacent the cutting portions of the same whereby the blades are prevented from yielding or partaking of a spring action which would be likely to cause chattering or result in improperly reamed holes. l

The invention is illustrated inFigure 5 in connection with a railroad or other heavy duty reamer having an elongated body 20 to which blades 22 are secured by retaining and binding strips 2%. Locking screws 26 are employed to secure the retaining and binding strips 24 in place. The outer edges of the blade 22 may be grooved transversely or substantially so as indicated at 28 to provide clearance for chips.

Figures 6, 7 and 8 illustrate a slightly modified form of invention wherein each blade 30 has a widened base which permits of the formation of a beveled shoulder 32 adapted to be engaged by the beveled edge surface 34 of a locking and binding strip 36. Particular attention is directed to the fact that the beveled surface 84 does not extend to the top or outer surface of the strip 36, but is formed by cutting away the lower corner of the strip to leave a portion of the inner edge of the strip flat as indicated at 37 for engagement with that portion of the blade immediately above thebeveled shoulder Therefore, it will be seen that each blade has a two point contact with the retaining strip thereof so that the blade is firmly held in an adjusted position in the groove. Cap screws 10 or similar fastening devices may be located at spaced points to secure the strips firmly in place and it is intended that there should be a very close fit of the various strips 36 between the blades and the side walls of the grooves. Particular attention is directed to the fact that the inner surface of each strip 36 is spaced from the bottom wall of the groove thereof to allow of the complete tightening of the cap screws.

A reamer constructed in accordance with this invention is provided with means whereby the various blades are securely and positively seated and are held in place with uniform pressure regardless of the strength of the reamer blade. Also the manufacture of reamers is greatly simplified and cheapencd by the employment of this invention and as the invention involves comparatively few parts, maintenance of the reamer at a low cost is achieved.

Having thus described the invention, what is claimed is; i r

its top surface lying in a plane intersecting the plane of said groove bottom, and the angle of which top shoulder surface with respect to the axis of said body being less than the angle of said groove bottom with respect to the axis, the bottom of the blade being adapted to seat upon the bottom of the groove and'the side of the groove opposite said shoulder being contiguous with the adjacent side of said blade, the other side of said blade being outwardly beveled at a uniform angle, the lower edge of said beveled portionlying in a plane substantially parallel with the plane of the top of said shoulder, the side of said blade between said beveled portion and the blade bottom being contiguous with the side of said shoulder and increasing in height in the direction of the inner end of the slot whereby to provide a contact surface of con-. siderable area beneath said beveled blade portion, a fastening strip in said groove and having one edge engaging the groove wall adjacent to and above said shoulder, said fastening strip having its opposite edge engaging the beveled side portion of saidblade, and means for forcing said strip toward said shoulder whereby to clamp the'blade in the slot and lock the same against withdrawal from the shallow end of the slot." Y

2. The combination set forth in claim 1 and said shoulder and the lower edge of said beveled blade portion lying in a plane substantially parallel with the axis of said body.

3. The combination set forth in claim 1 and said shoulder and the lower edge of said beveled blade portion lying in a plane substantially parallel with the axis of said body, and the means for forcing said strip into said slot comprising screws extending therethrough and into said shoulder, the distance between the top surface of said shoulder and the outer surface of said-body being considerably greater than the thickness of said strip.

4. A. reamer or the like comprising a body having a surface groove increasingin depth toward one end, a blade in said groove and having an outwardly and uniformly beveled surface at one side, the lower edge of such surface lying in a plane intersecting the plane of the bottom of said groove and the'angle of which with. respect to V the axis of the body is less than the angle of the plane of the bottom of the groove .with respect to the axis of the body, a fastening strip adapted to be forced into said groove and substantially co-extensive in length with said blade and shoulder, one'edge of such strip engaging one groove wall and the other edge of said stripengaging the beveled surface of said blade, the engagement of said strip with saidbeveled surface tend g, o

ture.

MARVIN C. DAWV. 

